I really do like the model. I was just about to start thinking where we could use this ;)
Because I can't really imagine the purpose of this building. You do mention what it does, granted. But where exactly does it fit into the game? Except for water + earth -> loam (which is already done by the foundry) everything else you describe is new stuff. I do not say that your object would not fit anywhere but just saying "it does crush gold to gold dust" is a bit weak. What is gold dust needed for? Where do you get granite chunks from?
As I see it this machine is a major change to existing production chain concepts and 'just so' introduces a few whole new objects/materials with no supporting concept on infrastructure. If you really want to bring in this ground shaking building, you should give more input on why it's needed and where everything belongs especially considering current settlement planning (see here).